An aim of modern medicine is to provide personalized or individualized treatment regimens. Those are treatment regimens which take into account a patient's individual needs or risks. A particularly important risk is the presence of a cardiovascular complication, particularly an unrecognized cardiovascular complication, or a predilection for such cardiovascular complications. Cardiovascular complications, particularly heart diseases, are the leading cause of morbidity and mortality in the Western hemisphere. Cardiovascular complications can remain asymptomatic for long periods of time. Therefore, reliable differential diagnosis of the presence of a cardiovascular complication is more difficult and error-prone than generally believed.
Specifically, patients suffering from symptoms of an acute cardiovascular event (e.g., myocardial infarction or MI) such as chest pain are currently subjected to a troponin T based diagnosis. To this end, troponin T levels of the patients are determined. If the amount of troponin T in the blood is elevated, i.e. above 0.1 ng/ml, an acute cardiovascular event is assumed and the patent is treated accordingly.
MI is classified as belonging to coronary heart diseases (CHD) and is preceded by other events also classified as belonging to CHD, like unstable angina pectoris (UAP). Symptomatic for UAP is chest pain which is relieved by sublingual administration of nitroglycerin. UAP is caused by a partial occlusion of the coronary vessels leading to hypoxemia and myocardial ischemia. In case the occlusion is too severe or total, a myocardial necrosis (which is the pathological state underlying myocardial infarction) results. MI may occur without obvious symptoms, i.e. the subject does not show any discomfort, and the MI is not preceded by stable or unstable angina pectoris.
UAP, however, is a symptomatic event preceding MI. A CHD in a subject may also occur symptomless, i.e. the subject may not feel uncomfortable or exhibit any signs of CHD like shortness of breath, chest pain or others known to the person skilled in the art. The subject, however, may be pathological and suffer from a malfunction of his coronary vessels which may result in an MI and/or congestive heart failure CHF, meaning the heart does not have the capacity to perform as required in order to ensure the necessary provision of blood to the subject's body. This may result in severe complications, one example of which is cardiac death.
It is known that subjects belonging to risk groups (e.g. smokers and diabetes patients) are more prone to suffering from CHD or CHF than subjects not exposed to risk factors (healthy subjects). Often, the asymptomatic forms of CHD/CHF occur, resulting in the pathological state remaining unrecognized. Hints for the occurrence of CHD are taken from the Framingham score or the PROCAM score. To date, the physiological conditions of the coronary vessels are generally evaluated by coronary angiography (invasive or virtual) being expensive and requiring elaborate and time-consuming procedures. Subjects which are not highly suspicious of suffering from a coronary vessel complication will in general not be subjected to coronary angiography.